The History of the 440 Six Pack - Chrysler's Ultimate Street Motor

Nineteen sixty-nine was a very good year for those Hamtramck high flyers; virtually every car Chrysler was producing was selling well. Stripper 170-cubeValiants and Darts, the darlings of the econo set, were being snapped up at a rapid rate. The sportier A-cars the GTS, Swinger, and 'Cuda — had already earned an enviable street reputation for maximum small-block performance. One punch and you knew that the 275-horse rating on the 340 was a bold-faced lie.

The B-motored B-bods were also doing quite nicely, thank you. The new trim, ragtop and air-grabber options, along with a new Technicolor bird, helped give the Road Runner a shot of adrenalin. Over at the white-hat department, the Dodge boys gave us the flush-grille Charger 500. Unbeknownst to us, that Charger would soon get a triple hormone shot and grow into the Daytona, that fabled winged warrior, complete with an Arnold Schwarzenegger-sized towel bar in back.

Only one thing was missing at intro time in the fall of 1968: new mills. The Chrysler crew was pretty much resting on their laurels, but who was complaining? The 340 was a dynamite mini-mill; the 383 was great for the buck, especially in its hot-cammed Road Runner and Super Bee incarnations. The 440 was the quintessential street piece and had been markedly improved for '68, what with a new Carter AVS jug replacing 1967's smallish AFB. The Hemi had been tuned-up, as well, for '68, receiving a warmer bumpstick grind. What could Chrysler possibly do for an encore?

The planners apparently had one mid-year trick up their sleeves: a special street racer option package for the 440 B-cars. What'd they do? Simple. They went to California and ordered a mess of Edelbrock hi-rise aluminum intakes cast for triple-deuce carburetion. They ordered a trio of Holley's best centerhung-float 2300 deuces, totalling 1,200 cfm. In the best Chrysler tradition, the whole setup was, of course, properly engineered. The carbs were each equidistant from their respective ports, so no cylinders were in danger of going lean. This permitted center-carb jetting, which, if driven sanely (but who could?), might even have delivered passable gas mileage.

Then, in the boldest move of all, they trashed the Road Runner and Super Bee's heavy steel hood and complex air-grabber setup and whipped up a batch of pin-on (no hinges!) fiberglass hoods. Bold decals on the Queen Mary-sized scoop announced to the competition what artillery you were packing ("440-6" on the Dodge, "440 6 BBL" on the Plymouth).

In another move designed to endear the car forever to street rats, they equipped every car, even automatics, with that grenade-proof axle setup, the Dana 60, complete with 4.10-to-1 gears and clutch-type Sure-Grip. No other axles were available. No air conditioning was available. No disk brakes were available. This was a street beater's dream car, to be sure.

To further the image, 15x6-inch wheels were shod with meaty G70-15
Goodyears, but no wheel covers or custom wheel were available. "Aha!" you think. "Dog dish hub-caps?" Nope. No hubcaps. Thinking like the street racers they surely were, the folks at Mopar let the car roll into the light of the Motown day wearing only chrome lug nuts. Talk about battle-ready!

The mill's internals saw a few mods as well, to ensure high-rpm integrity. Hemi valve springs and chrome-flashed valve stems combined with molly rings and a dual-point sparker to guarantee hi-rev action. A low-taper cam and tappet setup was designed to keep the bumpstick from acting like a GM piece and going away after a few runs. It worked.

Best of all, this entire package could be had for roughly half the price of the Hemi's $830.65 admission ticket. Street racers went wild, ordering them like lollipops. There was one obstacle to complete success, though. Edelbrock, basically a limited-production manufacturer, couldn't keep up with the demand for intakes. This, unfortunately, limited combined Dodge/Plymouth production to just 3,384 units. Naturally, this relatively low number doesn't hurt the collectibility or value of the cars today.

(This photo is of a 1967 four-barrel setup, not the Six Pack. Sorry!)

Rick Ehrenberg answered a reader’s question about fuels. He wrote, “Today's 93 "pump" (R+M/2) octane is roughly equal to 97 research octane. This is just barely — just barely — enough for a dead-stock 10:1 iron-head 440 when all is correct and there’s no carbon, with 180° antifreeze. If you still have detonation, make sure the TDC mark is accurate, the timing curve (advance rate) is stock, and the antifreeze is not over 180°F; and check to see if the heads have ever been milled or de-carboned. The engine probably needs more octane, a gallon or two of race gas in the tank. Any detonation you can hear is very bad and very destructive. Long term, the best fix is a pair of 440 source aluminum heads with Cometic gaskets.”

The '69 'Bee deserves special mention here. Since it was the first car to wear the Six Pack label, it is, of course, the image that pops into most Mopar gearhead's minds when someone says Six Pack. Sure, we know the '69 'Runner was the same car; it just didn't say Six Pack. The
Dodge name is the one that stuck.

Car Life, in its July 1969 issue, sang high praise of the car -- and in more than drag action. "Decent brakes" and "superpredictable and superresponsive" are phrases they used to describe the handling of the 'Bee, but their last paragraph said it all: ". . . a drag-strip terror; a Hemi equalizer; and a 3,800-pound, 117-inch wheelbase slalom car." Did these guys like the 'Bee, or what?

For 1970, Chrysler wasn't about to let a good thing slip through their hands again, so they tooled up for an in-house iron version of the manifold. They also vastly widened the motor's availability, making it an option for the 'Cuda, Challenger, Road Runner, Super Bee, GTX, Coronet R/T, Charger R/T and "winged-thing No. 2," the Superbird. Even land-yacht enthusiasts were happy in '70: The six-barrel monster wedge could be had in a C-body, the Sport Fury GT.

The mill's internals received a further upgrade for 1970, with gigondo con-rods heading the list. A new externally balanced extra-heavy-duty crankshaft was required with the new rods, and that in turn brought the requirement for external balancing, for the first time ever in a Mopar. A new right-side exhaust manifold, sporting an improved heat-control valve, was introduced. For the first time, automatic-equipped cars could be had with the 8 1/2-inch axle and highway gears, and the Dana was offered with your choice of 3.54 or 4.10 cogs.

Year

Horsepower

Pound-Feet

1969

390 @ 4,700

490 @ 3,200 (some sources say 3,600)

1970

390 @ 4,700

490 @ 3,200 (some sources say 3,600)

1971

385 @ 4,700

490 @ 3,200

1971 saw a virtual carry-over for the Six Pack setup. The engine was detuned a tad (the advance curve was fiddled with, mainly), to satisfy big brother's ever-tightening emissions noose. This backpedaling move cost only 5 ponies, not even enough to notice. The Six Pack, along with the Hemi and 340, were Chrysler’s only remaining high-compression (over 10-to-1 squeeze) mills.

1972? Yeah, we've seen the option sheets and brochures showing that the Six Pack was alive and well. It wasn't. Oh sure, maybe two or three sneaked out, but where are they? If you've got one, pump your garage full of nitrogen, then call us! We'll be right over!

Six Pack Rebop: Everything you need to know to rebuild the Six Pack on your 440 motor

Just five short years ago, trying to replace a missing Six Pack setup for your 440 muscle Mopar was a frustrating experience. Manifolds and carbs were swap-meet-only items, usually commanding big bucks for less-than-pristine merchandise. In recent years, though, the situation has improved radically. Holley has seen fit to reintroduce enough carburetors (six, in all) to be usable for every application. Edeibrock also saw the restoration/nostalgia scene coming, so they retooled to reproduce their '69-style aluminum manifold. The iron '70 to '71 manifold is gone forever, but since the '69 piece is lighter, looks almost identical and works as well (or better), so what?

Many of the fuel line, linkage and air cleaner pieces are, incredibly, still available from Chrysler. Anything else you might need -- including coil brackets, throttle cable and spring brackets -- is readily available from the various repro merchants.

So, today you can do what would have been impossible just a few years ago: assemble a Six Pack setup using all-new components. But you will have to make some compromises. For example, although the air-cleaner base ("retainer," in Mopar jargon) can still be had, the only one available are the later "splash shield" version. The shaker and 'glass-hood variations are history (but, hey, there's always the swap meets).

Holley is supplying the correct carbs for most '71s, but for both '69 and non-California '70s, they're substituting the '70 California Evaporation Control System (ECS) carbs. This represents absolutely no problem as far as performance is concerned, with one exception: As our carb-specification chart shows, the replacement center carb for the '70 to '71 cars is a bit on the lean side, especially for fresh-air cars. You should, therefore, probably consider rejetting the center carb to stock specs (if not a step or two richer) for your make and model. The bit of extra fuel at cruise can help prevent the lean-surge condition that bothered some of these cars when they were new.

Holley jets are readily available, and it's a five-minute job if performed before everything's bolted together. If the gaskets aren't reusable, be sure to use the new-style black cardboard gaskets (from Holley). They're unaffected by today's witches' brew gasoline.

The ECS carbs (especially the center carb) cause one minor annoyance, though. They look a little different from the original, non-ECS carbs. However, there's a simple remedy for that: Leave the air cleaner on at car shows!

If you're using the Six Pack setup in a non-stock environment (e.g., 310-degree cam, open headers), the stock jetting will need to be tinkered for maximum performance. Your best reference for this is Mopar Performance's Engine Performance Book, part No. P4349340. Holley also publishes and sells a whole library of tuneup, rework and parts books. An order form for these will be packed with the new carburetors.

One dark cloud has recently drifted into the otherwise-sunny parts scene: The air cleaner elements have been discontinued by both Mopar and Fram [Mike S. wrote that Chrysler also used Wix]. [Unless a new filter has been released since this was written], the only alternative is the reusable K-N oil-bath element. Now this is really not a bad idea anyway, especially on the 1969 cars, where one rainstorm and your $30 paper element was trash!

In the last few years, we've seen Six Pack setups find their way onto everything from pickup trucks to luxury Cordobas. The Six Barrel was flexible, street-smart inductions setup that performed as well as it looked. Pop the hood at Burger King and crowds gather. Take your Six Pack and attack the Bowties!

Relevant links

Quick 440 story (by Bob Marks)

Years ago, around 1986, I aquired a 1985 Dodge Ramcharger with the 360 engine. As an old hot-rodder, I wanted more. So I went on a quest.

I had a friend who had an old (1973 - not 1976 despite the photo caption ) Chrysler Imperial sitting in their driveway with a blown trans. They had decided to not repair it, but replaced the car, leaving the Imperial to just sit. Well, I did some investigation. It had a 440 RB engine in it with a 4-barrel. I made a deal with them, bought the whole car for the drive train, and then had another friend tow
the car to my house, where we removed the engine and trans, and I then gave the car shell to my
tow-friend.

I bought an engine stand from PAW to store this behemoth on, but after I got it, and put the intact engine on it, the stand bent! When I called PAW up, they said that the stand that they had sent me was intended for small-block Chevys, not the big Chryslers! So I sent them back the stand, and they sent me a HUGE 4-wheeled stand that they said was rated for 1000 lbs. When I put this engine on the new stand, using extra bolts at the bell housing, the front of the engine still
did a dip, so I had to put a prop rod under the crank damper to keep the front up, for insurance!

I had wanted this particular engine for my hop-up because my research informed me that it was
the last of the thick-wall castings, with dog-bone shaped water passages, that had been added for motor-home use, and was the last of the forged crank, forged rod engines built in this size by Chrysler.